In the stearns passage, what deadly illness arrived from southern asia?

The correct answer is measles.

In the Stearns' passage, measles arrived from southern Asia.

Measles is a infection caused by measles virus. Symptoms usually develop 10–12 days and last to 7–10 days. Typical symptoms are  cough, runny nose, fever, high temperature.

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.